Polystyrene foam, such as expanded polystyrene (EPS), has many industrial applications, for example, in the food industry as cups and containers. However, such polystyrene-based products suffer from significant drawbacks such as uneconomical recycling as well as lack of biodegradability. Polystyrene foam, and especially expanded polystyrene foam, creates a recycling issue due to its low bulk density. Transporting polystyrene foam to a recycling plant becomes quite expensive, since polystyrene foam takes a lot of space per weight because of its low bulk density. The waste polystyrene foam is transported, usually by truck, from the restaurant to waste facility. However, given the large volume of polystyrene foam and EPS relative to its weight, transportation becomes extremely inefficient (as only a fraction of the maximum weight capacity of the truck is utilized). This results in significantly more costs (fuel, time, etc.) in transporting the same weight of EPS as compared to regular waste.
Others have tried to solve this problem with limited success. For example, some have tried to compact the polystyrene foam to increase its bulk density, i.e., to lower its volume per weight. However, such methods to compact polystyrene foam are typically very expensive as special equipment is required to recycle polystyrene foam products. Another approach to recycling of EPS is to chemically to reduce the EPS volume. However, there are significant drawbacks utilizing these chemicals as such chemicals can be very hazardous to human health and to the environment, as well as have storage, transportation and stability issues. Other chemicals, for example terpenes, have storage and transportation issues because of their flash point and are highly volatile.